<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>

</body>
<script>
    //函数运行在严格模式底下
   /*
       "use strict"
       function testStrict() {
            console.log(this)
       }
       testStrict();
   */


   //函数在严格模式底下被调用
   function testStrict() {
       console.log(this);
   }

   (function () {
       "use strict"
       testStrict();
   })()
</script>
</html>